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[Licence| Download | New Version Template] aeki_v2_0.tar.gz(2094 Kbytes)
Manuscript Title: PACIAE 2.1: An updated issue of the parton and hadron cascade model PACIAE 2.0
Authors: Ben-Hao Sa, Dai-Mei Zhou, Yu-Liang Yan, Bao-Guo Dong, Xu Cai
Program title: PACIAE version 2.1
Catalogue identifier: AEKI_v2_0
Distribution format: tar.gz
Journal reference: Comput. Phys. Commun. 184(2013)1476
Programming language: FORTRAN 77 or GFORTRAN.
Computer: DELL Studio XPS and others with a FORTRAN 77 or GFORTRAN compiler.
Operating system: Linux or Windows with FORTRAN 77 or GFORTRAN compiler.
RAM: ≈ 1G bytes
Keywords: Relativistic nuclear collision, PYTHIA model, PACIAE model.
Classification: 11.1, 17.8.

Does the new version supersede the previous version?: Yes

Nature of problem:
PACIAE is based on PYTHIA. In the PYTHIA model, once the generated particle/parton transverse momentum (pT) is randomly sampled, the px and py components are randomly placed on the circle with radius of pT . This strongly cancels the final state transverse momentum asymmetry developed from the initial spatial asymmetry.

Solution method:
The px and py component is now randomly placed on the circumference of an ellipse with half major axis of pT(1+δp) and the half minor axis of pT(1-δp) instead of circle.

Reasons for new version:
PACIAE is based on PYTHIA, where once the generated particle/parton transverse momentum (pT) is randomly sampled, the px and pyy components are randomly placed on the circle with radius of pT. This is not only strongly canceling the final state transverse momentum asymmetry developed from the initial state spatial asymmetry but also inconsistent with the ATLAS observation of the final state charged particle transverse sphericity is less than unity [1].

Summary of revisions:
The main revision is executed by randomly placing px and py components of the generated particle/parton transverse momentum pT on the circumference of an ellipse with half major axis of pT(1+δp) and the half minor axis of pT(1-δp) instead of circle.

Restrictions:
Depends on the problem studied.

Running time:
  • Using the supplied input file of usux.dat (where the string fragmentation is selected and the elastic parton-parton interactions is considered only, the same later) to run 1000 events for the √s=200 GeV Non Single Diffractive pp collision by 21a.tar.gz takess 0.5 minute.
  • Using the supplied input file of usu.dat to run 10 events for the 10-40% most central Au+Au collisions at √sNN=200 GeV by 21b.tar.gz takes 5 minutes.
  • Using the supplied input file of usu.dat to run 10 events for the 10-40% most central Au+Au collisions at √sNN=200 GeV by 21c.tar.gz takes 17 minutes.

References:
[1] ATLAS Collaboration, arXiv:1206.2135v1